refactor: separate Flash PDF inline evidence processing

mineru/model/flash/pdf/inline/__init__.py

@@ -0,0 +1,4 @@
+# Copyright (c) Opendatalab. All rights reserved.
+"""按职责拆分的 Flash PDF 内部实现。"""
+
+__all__: list[str] = []

mineru/model/flash/pdf/inline/common.py

@@ -0,0 +1,113 @@
+# Copyright (c) Opendatalab. All rights reserved.
+"""提供行内证据共享的字符和几何规范化原语。"""
+
+from __future__ import annotations
+
+import math
+from typing import Any, Iterable, cast
+
+from .....types import BBox
+from .types import (
+    _LIGATURE_REPLACEMENTS,
+    _PDF_CONTROL_CHAR_RE,
+    _PDF_SEPARATOR_SPACE_CHARS,
+    _PDF_ZERO_WIDTH_CHARS,
+    PDF_TEXT_STYLE_ORDER,
+    PDFTextStyle,
+    PDFTextStyleLine,
+)
+
+
+def _style_line_reading_order_key(
+    line: PDFTextStyleLine,
+) -> tuple[int, float, float]:
+    """优先使用原生 source_index 排序，重复索引时再以 bbox 保持稳定。"""
+
+    return line.source_index, line.bbox[1], line.bbox[0]
+
+
+def _coerce_bbox(value: Any) -> BBox | None:
+    """把 list、tuple 或 pdftext bbox 对象收敛为合法有限 bbox。"""
+
+    raw_bbox = getattr(value, "bbox", value)
+    try:
+        if raw_bbox is None or len(raw_bbox) != 4:
+            return None
+        bbox = tuple(float(item) for item in raw_bbox)
+    except (TypeError, ValueError):
+        return None
+    if not all(math.isfinite(item) for item in bbox):
+        return None
+    if bbox[2] <= bbox[0] or bbox[3] <= bbox[1]:
+        return None
+    return bbox  # type: ignore[return-value]
+
+
+def _ordered_line_chars(line: Any) -> list[dict[str, Any]]:
+    """按 char_idx 修复异常乱序字符，同时保留缺少索引时的来源顺序。"""
+
+    chars = [char for char in getattr(line, "chars", []) if isinstance(char, dict)]
+    indexed_chars = [char.get("char_idx") for char in chars]
+    if (
+        chars
+        and all(isinstance(index, int) for index in indexed_chars)
+        and any(first > second for first, second in zip(indexed_chars, indexed_chars[1:]))
+    ):
+        return sorted(chars, key=lambda char: int(char["char_idx"]))
+    return chars
+
+
+def _normalize_match_fragment(value: Any) -> str:
+    """把单个字符片段规范为忽略排版空白的确定性匹配文本。"""
+
+    output: list[str] = []
+    for char in str(value or ""):
+        if char in _PDF_ZERO_WIDTH_CHARS or char == "\u00ad":
+            continue
+        if char == "\x02":
+            output.append("-")
+            continue
+        if char.isspace() or char in _PDF_SEPARATOR_SPACE_CHARS:
+            continue
+        if _PDF_CONTROL_CHAR_RE.fullmatch(char):
+            continue
+        output.append(_LIGATURE_REPLACEMENTS.get(char, char))
+    return "".join(output)
+
+
+def _canonical_styles(styles: Iterable[str]) -> tuple[PDFTextStyle, ...]:
+    """按公开富文本协议顺序过滤、去重并规范样式集合。"""
+
+    style_set = set(styles)
+    return cast(
+        tuple[PDFTextStyle, ...],
+        tuple(style for style in PDF_TEXT_STYLE_ORDER if style in style_set),
+    )
+
+
+def _bbox_intersection_area(first: BBox, second: BBox) -> float:
+    """返回两个合法 bbox 的相交面积。"""
+
+    width = max(0.0, min(first[2], second[2]) - max(first[0], second[0]))
+    height = max(0.0, min(first[3], second[3]) - max(first[1], second[1]))
+    return width * height
+
+
+def _bbox_overlap_ratio(first: BBox, second: BBox) -> float:
+    """返回 first 面积中落入 second 的比例。"""
+
+    intersection_width = max(0.0, min(first[2], second[2]) - max(first[0], second[0]))
+    intersection_height = max(0.0, min(first[3], second[3]) - max(first[1], second[1]))
+    first_area = max(0.01, (first[2] - first[0]) * (first[3] - first[1]))
+    return intersection_width * intersection_height / first_area
+
+
+__all__ = [
+    "_style_line_reading_order_key",
+    "_coerce_bbox",
+    "_ordered_line_chars",
+    "_normalize_match_fragment",
+    "_canonical_styles",
+    "_bbox_intersection_area",
+    "_bbox_overlap_ratio",
+]